RU226751U1 - VEHICLE TRANSMISSION - Google Patents

Abstract

The utility model relates to transport engineering, namely to vehicle transmissions. The technical result of the proposed solution is to reduce the noise level of the vehicle gearbox while maintaining strength and power loads. The technical result is achieved by the fact that in a vehicle gearbox containing primary, secondary and intermediate shafts, the primary and secondary shafts are installed coaxially, and the intermediate shaft is located parallel to the mentioned shafts, while the primary shaft is in constant gear engagement with the intermediate shaft, and the intermediate shaft gears are in constant engagement with gears freely mounted on the secondary shaft, the gear clutches are located between the secondary shaft gears and are rigidly engaged with the secondary shaft with the ability to move along it in the longitudinal direction, while the gear clutches are engaged with the shift forks gears interacting with the rollers connected to the gear shift lever, according to the claimed utility model, the constant gear transmission uses fine-module gearing with module m=2.26 without changing the center distance of the shafts and the transmitted torque from the engine. 1 ill.

Description

The proposed device relates to transport engineering, namely to vehicle transmission.

Vehicle gearboxes are designed to obtain the optimal torque value on the transmission secondary shaft at any speed.

One of the important aspects of a vehicle's gearbox is its noise level.

To reduce the noise of gearboxes, various methods are used, in particular:

optimization of the shape of gear teeth (the use of gears with an involute profile can improve engagement and reduce noise);

the use of hellers (the use of special curved teeth on gears that improve the smoothness of engagement);

noise insulation of the housing (use of noise-absorbing materials in the gearbox housing to minimize the transmission of vibration and noise to the outside);

changing gear materials (using softer or composite materials that can reduce vibration transmission).

Another approach to solving the problem of reducing gearbox noise is to reduce the gear module.

The closest analogue in technical essence and the achieved effect is a vehicle gearbox containing primary, secondary and intermediate shafts, with the primary and secondary shafts installed coaxially, and the intermediate shaft located parallel to the mentioned shafts, while the primary shaft is in constant gearing with the intermediate shaft, and the intermediate shaft gears are in constant engagement with gears freely mounted on the secondary shaft, the gear clutches are located between the secondary shaft gears and are rigidly engaged with the secondary shaft with the ability to move along it in the longitudinal direction, while the gear clutches are in mesh with gear shift forks interacting with rollers connected to the gear shift lever, with the constant gear transmission module equal to 2.605 [RU 143 686, B60K 17/08, publ. July 27, 2014].

The disadvantage of the known solution is the noise level of operation.

The technical problem of the proposed utility model is the optimization of the gearing parameters of the vehicle gearbox.

The technical result of the proposed solution is to reduce the noise level of the vehicle gearbox while maintaining strength and power loads.

The technical result is achieved by the fact that in a vehicle gearbox containing primary, secondary and intermediate shafts, the primary and secondary shafts are installed coaxially, and the intermediate shaft is located parallel to the mentioned shafts, while the primary shaft is in constant gear engagement with the intermediate shaft, and the intermediate shaft gears are in constant engagement with gears freely mounted on the secondary shaft, the gear clutches are located between the secondary shaft gears and are rigidly engaged with the secondary shaft with the ability to move along it in the longitudinal direction, while the gear clutches are engaged with the shift forks gears interacting with the rollers connected to the gear shift lever, according to the claimed utility model, the constant gear transmission uses fine-module gearing with module t = 2.26 without changing the center distance of the shafts and the transmitted torque from the engine.

Fine-modulus gearing is commonly used in precision engineering. Fine-modulus gearing is a type of gearing that uses wheels with a relatively small tooth module. The gear module is a parameter characterizing the size of the teeth; it is measured as the ratio of the diameter of the pitch circle of a gear to the number of its teeth.

It is a known fact that for quieter and smoother operation of a gear transmission under constant loading conditions, a minimum module of gear wheels should be assigned (Rudnitsky V.N. Influence of geometric parameters of gear wheels on noise in gear transmissions / V.N. Rudnitsky. Collection of articles. Contribution scientists and specialists in the national economy / BGITA - Bryansk, 2001. - p. 125-128).

Gear modulus is a measure of the size of the teeth and essentially relates to the torque that the wheel can transmit. Reducing the module leads to a reduction in the size of the teeth, which provides smoother engagement, which, accordingly, reduces vibration and noise in the gears.

In the claimed design of the vehicle gearbox, the parameters of the gears are optimized without changing the center distance of the shafts and changing the transmitted torque from the engine, which ensures a reduction in the noise level of the vehicle gearbox.

The test results of the claimed solution and the closest analogue are presented in the test report dated March 22, 2024 No. 040 of the testing center of EvraseTest LLC, registration No. ROSS II.31714.04SITs0.05.

conclusions

After optimizing the gearing parameters in a constant gear transmission, the following results were obtained:

the module is reduced to m=2.26 instead of m=2.605, while maintaining the center distance of 78 mm,

Noise decreased from 83-84 dBA to 81-82 dBA during gearbox operation, due to the use of fine-module gearing in the transmission of constant gearing while maintaining the strength characteristics of the vehicle gearbox.

The vehicle gearbox is illustrated by a drawing showing a cross-section of the gearbox.

The vehicle gearbox (figure) contains an input shaft 1, which is connected through a clutch to the engine flywheel (not shown in the figure). The secondary shaft 2 is rigidly connected to the driveshaft and then to the axle, gearbox and wheels (not shown in the figure). Intermediate shaft 3 is designed to transmit rotation from primary shaft 1 to secondary shaft 2. Primary 1 and secondary 2 shafts are installed coaxially, intermediate shaft 3 is located parallel to shafts 1, 2. On intermediate shaft 3 there are gears of the first 4, second 5, third 6, fourth 7, fifth 8 gears, which rotate freely on the hubs (not shown in the figure). The gear clutches 9 are rigidly fixed to the splines of the secondary shaft 2 and can move along them along the secondary shaft 2. The gear clutches 9 are engaged with the gear shift forks 10 interacting with the rollers connected to the gear shift drive (not shown in the figure) and gear shift lever 11.

The operating principle of a vehicle transmission comes down to a kinematic connection at different stages of the primary and secondary shafts with different combinations of gears with different gear ratios. Torque is transmitted from the car engine to the input shaft 1, which is in constant gearing with the intermediate shaft 3. Gears 4, 5, 6, 7, 8 of the secondary shaft 2 are in constant gearing with the gears of the intermediate shaft 3. Gear clutches 9 are rigidly fixed on the secondary shaft 2. By means of the gear shift lever 11, the gear shift fork 10 is selected and axially moved, which engages the gear clutch 9 with the gear of the required gear, thereby closing the kinematic chain and transmitting the required gear ratio to the secondary shaft 2 and then onto the driving wheels of the vehicle.

After optimizing the gear parameters of the claimed vehicle gearbox, the following results were obtained:

Constant gear transmission:

The module is reduced from m=2.605 to m=2.26.

The number of decibels (dBA) has been reduced from 83-84 to 81-82. Thus, the noise level of the claimed vehicle gearbox is reduced.

Claims (1)

A vehicle transmission comprising a primary, secondary and intermediate shafts, wherein the primary and secondary shafts are mounted coaxially and the intermediate shaft is positioned parallel to said shafts, wherein the input shaft is in constant gearing with the intermediate shaft, and the intermediate shaft gears are in constant meshing with gears freely mounted on the secondary shaft, the gear clutches are located between the gears of the secondary shaft and are rigidly engaged with the secondary shaft with the ability to move along it in the longitudinal direction, while the gear clutches are engaged with the gear shift forks interacting with the rollers connected with a gear shift lever, characterized in that the constant gear transmission uses fine-module gearing with module m=2.26 without changing the center distance of the shafts and the transmitted torque from the engine.